4-Hexylresorcinol is a compound that has been described for topical use to lighten skin, for use in oral antiseptic lozenges, and other uses. However, 4-hexylresorcinol has been described and recognized as “water insoluble.” As such, formulation of 4-hexylresorcinol in combination with water has been rather limited. Typically, formulation of 4-hexylresorcinol with water has involved, for example, premixing 4-hexylresorcinol in a glycol such as ethoxydiglycol, and diluting this mixture to low concentrations of 4-hexylresorcinol by adding various other ingredients, including water. The process may also involve heating as well.
It has now been discovered, however, that mixtures of 4-hexylresorcinol and water may be made, particularly mixtures having high concentrations of 4-hexylresorcinol. Such mixtures may, for example, be used to deliver 4-hexylresorcinol to formulations without the need for additional solvents, solubilizers, and the like. In particular, an aqueous concentrate comprising about 64% to about 80% by weight of 4-hexylresorcinol is easily handled and used to make a variety formulations and compositions. Advantageously, such an aqueous concentrate is surprisingly high in clarity.